Ice cube tray



Dec. 23, 1947. J. A. Grrs 2,433,210

ICE CUBE TRAY Filed Feb. 2, 1945 2 Sheets-Sheet l Dec. 23, 19477 J. A.GlTs IcE cuE TRAY Filed Feb. 2, 1945 2 Sheets-Sheet 2 j A @V zh IPatented Dec. 23, 1947 ICE CUBE TRAY Joseph A. Gits, Chicago, Ill.,asslgnorof one-half to Jules P. Gits, Chicago, Ill.

Application February 2, 1945,` Serial No. 575,798 14 claims. (ci.ia-108.5)

This application is a continuation in part of application Serial No.418,753, filed November 12, 1941, which has become abandoned.

This invention relates to ice freezing trays adapted for use inrefrigerators or the like for freezing a plurality of ice cubes.

Freezing trays used in refrigerators for producing ice cubes have beenlargely made of metal and of rubber, but the vshortage, of thesematerials has presented a real problem to the manufacturer. While metalis a good conductor of heat and permits freezing to be effected in vaminimum period of time and rubber may be distorted to .eilect quickemptying ofthe cubes, both materials are of `a character that is knownas frost forming and permit frost to build up rapidly along the sides ofthe trays and cause the same to be solidly frozen in the freezingchambery if left for a considerable period of time. other hand, thesedevices have been built as single trays which merely divide the interiorinto compartments by partitions, thereby exposing the outer and bottomsides only of the outer compartment's and the bottom side of the innercompartments. The freezing action was accordingly delayed and theremoval of the ice cubes made difllcult. y

An object of the present invention is to provide an improved, simple andefficient form of structure for freezing trays, which may beadvantageously made of a thermoplastic material capable of being moldedin a single operation and providing maximum heat conducting surfaces foreach compartment in which an ice cube is frozen.

A further object of the invention is to provide a freezing tray ofimprovedvstructure that may be made of a thermoplastic material whichtends to retard frost formation upon the exposed outer' On the surfacesand to which the ice d-oes not necessarily tend to adhere so that theice cubes may be readily dislodged or removed. Y

A still further object of the invention is to provide a freezing' trayof thermoplastic material that is somewhat resilient so that the traymay be twisted slightly to loosen the ice cubes Within the variouscompartments and thereby be removed witliout imparting heat to the outersurfaces before the cubes can be removed.

It is also an object of this invention to provide an improved, simpleand efficient form of thermoplastic structure which may be twistedslightly to loosen the ice cubes `in the compartment and which isprovided with a simple means A of limiting this twisting action wherebyto pre-f vent permanent distortion ,of the tray.

Other objects andadvantages` of the invention-5,

will be apparent f-romthe following detallde scription when taken inconnection with the accompanying drawings, which form a part hereof.

In the drawings:

Figure 1 is e. perspective view of a tray em-k bodying the invention; AY

Fig. 2 is a side elevational view of this tray;

Fig. 3 is a longitudinal sectional view takenv floor or bottom of thefreezing chamber which.v may be used in connection with the'tray toeffect rapid freezing of the liquid in the tray;

Fig.` 9 is a transverse sectional view of the cooling chamber .but showndiagrammatically for illustrationpurposes only,l together with the trayin end elevation to.l illustratethe use of the bottom platel'shwn inFig. 8; C

Fig. 10is amodifled formpf this bottom plate of the cooling chamber thatmay also be used in connection with'- the tray disclosed herein;

Fig. 11 is a'fragmentary perspective view illustrating the tray seated-upon this modified form-I Fig. 12 illustrates a further 4modification fwherein the tray is associated with a separate dish-like memberembodying the principledisclosed in connection `with `the use of thebottom'l plates shown in Figs. 8 and 10, this dish-like member beingadapted for .removal from the cooling chamber with the tray.

For the purposes of illustration, I have shown one form of embodiment ofthe invention. It is,

to be understood that this structure merely illustrates the inventionherein disclosed so that those skilled in the art will be readily taughthow to practice the invention.

The ice cube or freezing trayy I comprises a plurality of individualcompartments 2 which may be arrangedin anyrcell-like pattern, for exfample, as shown, intwo rows, and may be of any desirable shape, say,square, so as to produce true cubes of ice-if they are of the'samedepth, or rectangular in cross section so as to produce small pieces ofice, which, while not true'cubes,

are considered.. i2usuch in the art and will be con;- K-

. 3 sidered as such for the purposesof this disclosure. Each compartment2 is defined by four side walls I. 4. 5 and 8, and a bottom wall 1. Theinner side walls may be designated l and the outer side walls may bedesignated 3. These side walls and the bottom merge into slightlyrounded outside corners 8 which eil'ect rounded inside corners 9 at thebottom and the top and along the sides oi' each compartment. Theserounded corners have been found to facilitate removal of the cubes andalso to enhance the appearance ci' the tray.

'I'he upper portion of the side walls 3 to v6, inclusive, merge intowhat may be called an upper wall or ledge I that extends about all sidesof the tray as well as between rows longitudinally of the tray andcrosswise of the tray between adjacent compartments 2 of each row. 'I'hewalls are designed to slant inwardly from the top to give an inwardtaper to each compartment and to further provide air spaces Il crosswiseof the tray between adjacent compartments of each row and an air spacel2 that runs longitudinally of the tray between the two rows andseparates inner walls d, this being illustrated in Figs. 3 to 5,inclusive. The upper outer surface of wall 3 is given a slightly greaterslant at i3 which merges with the upper face l0 to form in effect asubstantial rim-like shoulder or ledge, as before mentioned, thatextends along the outer top edges of the tray. The slanting inside wallsd merge at M to form the central part or ledge separating the two rowsof compartments. The slanting side walls 5 and t also merge at l5 toform the part of the upper wall lll or cross ledge between adjacentcompartments of the same row, and, if the compartments of these rows arein alignment, as shown, the cross ledge extends from one to the otherside of the tray. The general design efiects a very substantialstructure across the top face of the tray which accomplishes certainadvantages in the type of construction shown, as will be presentlydescribed.

The effect to be given by the arrangement described is that eachcompartment presents the appearance of an individual relatively smalltray suspended from a top plate having holes cut therein that define thevarious compartments. I preferably extend one end of the tray at theupper wall or ledge l0 to form a forwardly curved handle portion i6, thesame being of relatively substantial thickness at the juncture andtapering toward the outer edge so that a substantial mass of materialisA provided along this front edge for a purpose also to be presentlydescribed.

I find that any suitable synthetic resin that is thermoplastic may beused and mention specifically ethyl and acetate cellulose because,within certain limits, they are slightly springy in character, will notsoil when handled and may be made in different colors. Although thelatter two features are not considered essential with respect to thepresent invention, it is desirable to use a plastic that will not befrost forming and to which ice will not freeze. Consequently, thematerial being resilient or springy in character, the tray may betwisted as shown in Fig. 6 and the ice cubes will be immediately freedfrom the compartments 2. I find that a plastic material is particularlydesirable because it may be gripped without causing cold burns whichoccur in the case of metal trays.

Although thermoplastic material has certain desirable characteristicsmaking the material particularly desirable for use in the constructionof an ice cube tray and although difliculties heretofore experienced inits use and handling have been overcome, this material does not conductheat as rapidly as metal. For this reason, it is found that theindividual arrangement of compartments 2 and providing separate sidewalls for each compartment assures maximum heat conducting surfaceswhereby the freezing period is reduced to a minimum. Also, it is foundthat slanting the side walls additionally provides not only air spacesbetween the walls of adjacent compartments but allows these air spacesto be increased in size without materially decreasing the capacity ofthe compartments. When the tray is placed in a cooling chamber, the heatis rapidly conducted from the walls so that the liquid in thecompartments may be brought to a freezing temperature as rapidly aspossible.

In Figs. 8 to 12, inclusive, various forms of bottom plates for thecooling chamber are illustrated, which may be used with the tray shownherein for the purpose of still further reducing thc freezing time ifdesired. In Fig. 8, bottom plate 25 is illustrated with a tapered rib 26adapted to act not only as a guide for the tray when it is slid back andforth in cooling chamber 2l, but also as a heat conducting element indirect contact with the inside walls i of compartments 2 to facilitate arapid cooling action. The tapering of air space l2 permits this rib 2Bto be tapered, if so desired. Tapered ribs 28 may be providedtransversely upon the bottom plate 29, shown in Fig. l0, for lying, 1fso desired, in the air spaces extending crosswise of the tray betweenthe compartments. A tapered rib 30 disposed longitudinally upon plate 29is also provided in this instance to lie in this air space i2 extendinglengthwise of the tray between the two rows of compartments 2. Themanner in which the tray will seat upon this type of bottomfplate isillustrated in Fig. 11. Transverse tapered ribs 28 are nested intransverse air spaces i i in substantially the same manner as thelongitudinal rib 3U. These ribs are also tapered so as to engage sidewalls 5 and 6, as well as the walls Il. In this instance, it will benecessary to lift the tray up in order to clear these ribs before it maybe removed from the cooling chamber. However, the cooling chamber may beof a depth permitting such lifting of the tray. Either bottom plate 25or 29 may be provided with side ribs 35 shown in Figs. 8 and 9, whichembrace the outer surfaces of walls 3 to increase the heat conductingaction therealong. These ribs 35 may be higher than ribs 2S, 28 and 30,which can extend into spaces Il and I2 only to the height of the webs orpartitions 33 and 34.

Figl2 illustrates a further embodiment of the bottom plates 25 and 29,illustrated in Figs. 8 and 10. In this instance, the tray is adapted tobe first seated in a dish-like member or pan 3| before it is inserted inthe cooling tray. Member 3l may have either the single longitudinal rib28, or the combination of transverse ribs 28 and a longitudinal rib 30,as illustrated in Fig. l0. Member 3| may be provided in instances wherethe bottom plate of the cooling chamber is not furnished with thesetapered ribs and it is desired to secure the reduced cooling periodafforded by the use fo such ribs in direct contact with the walls ofcompartments 2.

The structure herein provided also permits the provision of openings orair passages 32 at the juncture of adjoining pairs of compartments sothat it is possible to assure a relatively uniform thickness of wall foreach compartment and eliminate thereby any uneven l freezing actionwhere the conduction of heatV may not be as rapid. As previouslymentioned, the tray may be twisted to dislodge the ice cubes from thecompartments, as shown in Fig. 6. This may be accomplished becauseplastic material is somewhat resilient in character and is susceptibleto deflection, but I yhave found that plastic material maybepermanentlyl distorted when twisted in this, manner. The individualconstruction of the compartments permits a certain resiliency in thestructure shown but to preventy this structure from beingV permanentlydistorted when the tray is flexed,

' tion with the top face or rim-like shoulder I3 that extends about thetray to provide a very substantial structure and aid in conducting heatfrom compartments 2. They will also prevent a twisting action that isapt to cause distortion. I find that these webs or partitions 33 and 34novelly cooperate in the general design herein disclosed to provide avery efficient type of tray made of plastic material. They permit theindividual construction of each compartment with separate wallsfor eachcompartment and stillprevent excessive flexing that would otherwiseresult Iin permanent set or breakage of the tray. They also provide asubstantially solid top portion from which the walls of each compartmentextend so that the tray is made sufficiently rigid to retain its shapeeven though subjected to abuse and rough handling that is apt to occurin the normal use of anice cube tray. Ledges I0, I4 and I5 function totransmit thev torsional twist throughthe entire body ofthe tray. Asstated, connecting webs v33 and 34 tend to limit this torsional twisttransmitted by the ledges, and further, by this limiting action theydistribute the torsional twist to flex the side walls 3, 4, 5 and 6individually, and, of course, the bottom wall 1 by the flexing of thesesidewalls. In otherl words. the webs 33 and 34 serve a dual function,and therefore, novelly cause the side and bottom walls of eachcompartment 2 to flex,thereby releasing, or aiding in releasing, the icecubes.

Thermoplasticvmaterial permits the handling of the tray with cubesfrozentherein without the freezing of thehands tothe outside surfaces ofthetray walls. Moreover, the tray may be handledfwith greater facility.It will not scratch or chip porcelain bodies and highly finishedsurfaces when dropped thereon. If dropped, the tray willnot break norbecome dented and will not cut a linoleum covered surface as in the caseof metal.' Moreover, these desirable features are augmented in thepresent case because the construction permits ready gripping to free thecubes :A V'further advantage resides in the fact that niqueconstructionmay be made in a single 'duction of a perfect articlewherein the strains,

if, ,a l 1y, are uniformly distributed. Fig. '7 illusoperation,preferably by'inj'ection molding under l 'relatively high pressureswhich assures the protratesfsomewhat diagrammatically a die 40 which maybe used. This die 40 comprises two separable parts 4I and 42 betweenwhich a cavity 43 is provided, Thiscavity 43 is of a shape correspondingto that of the tray and communicates with the sprue 44 by any suitablenumber of passages 45. The finished product may be formed in this mannerby a single operation which reduces the cost of manufacture by anappreciable margin over metal formed trays requiring a -number ofoperations, both in the forming and in the assembling.

From the foregoing description it will be apparent that a simple,practical and improved form of ice cube or freezing tray is providedthat embodies and provides for features of advantage ndt heretoforeobtained. The u-se of thermoplastic material permits making a structurewhich is highly desirable, while the structure itself accomplishesadvantages as to the time requiredto freeze and thereafter as to theease of removal of the cubes. The ice cubes do not tend to adhere to thethermoplastic material while the resilient characteristic of thisthermoplastic material can be used in connection with the design of theconstruction to free the ice cubes quickly without permitting the use ofexcessive twisting that will crack or permanently destroy the tray.

Without further elaboration, the foregoing will so fully explain thegist of my invention that others may, by applying current knowledge,readily adapt the same for use under varying conditions of service,without eliminating certain features, which may properly be said toconstitute the essential items of novelty involved, which items areintended to be dened and secure-dto me bythe following claims.

I claim:

1. An -ice freezing tray comprising a molded body of thermoplasticmaterial characterized by a resiliency permitting flexing to free theice, separately formed compartments having their walls integrally formedand integrally united along their top edges to the walls of adjacentcompartments, the walls between adjacent compartments below their topedges being separated by air spaces to provide for individually exposedheat conductiong surfaces for each compartment, said molded body beingtwistable to iiex said walls, and integrally formed transverse ribsbridging said air spaces and connecting the walls of adjacentcompartments tolimit the* flexing of said walls when said molded body istwisted to free the bodies of ice in said compartments.

2. An ice freezing tray comprising a molded body of thermoplasticmaterial characterized by va resiliency permitting flexing tofree theice,

separately formed compartments having their walls integrally formed andintegrally united along their top edges to the walls of adjacentcornpartments, the walls between'adjacent compartments below their topedges being separated by air spaces to provide for individually exposedheat conducting surfaces for each compartment, said molded body beingtwistable to iiex said walls to free the bodies of ice in saidcompartments, a row of segments ofsaid thermoplastic material disposedin a plane parallel tothe longitudinal center line of said tray andconnecting'opposing walls of adjoining compartments for a portion'of thedepth of said compartments.

3. An icesfreezing tray comprising a body of thermoplastic materialhaving a pluralityof compartments, each compartment having side wallsand a bottomwall that are of continuousfformation with respect to eachother, the side walls being united adjacent their top edges to the sidewalls of adjacent compartments, certain of the side walls taperinginwardly to provide tapered air spaces between the opposing side wallsof adjacent compartments, and bracing means bridging said air spacesbetween the opposing side walls of adjacent compartments to interlockall of said compartments at said side walls as well as adjacent the topedges thereof.

4. An ice freezing tray comprising a body of thermoplastic materialformed into a plurality of compartments, each compartment havingindividual walls, the side walls of adjoining compartments being joinedtogether along their upper edges, said material and said wallsbeingexible to cause the walls temporarily to deform and thereafter toreturn to .their normal condition whereby to release the frozen mass ineach compartment when said body is gripped at opposite ends andtorsionally twisted, the material along the upper edges where said wallsare joined transmitting said torsional twist through the entire body,and limiting ribs between walls of adjoining compartments restrictingsaid torsional twist so as to distribute the same throughout the body tosecure flexure of the individual walls of each compartment without adistortion of the material that will cause a permanent set or fractureof the material.

5. A freezing tray comprising a body of thermoplastic material formedinto a plurality of compartments, the side walls oi adjoiningcompartments being joined together along one edge, said material andsaid walls being flexible to cause the walls temporarily to deform andthereafter to return to their normal condition whereby to release thefrozen mass in each compartment when said body is gripped at oppositeends and torsionally twisted, the material where joining the side wallsof adjoining compartments transmitting said torsional twist through theentire body, and limiting ribs between walls of adjoining compartmentsrestricting said torsional twist so as to distribute the same throughoutthe body to secure flexure of the Walls of the compartments withoutdistortion of the material that will cause a permanent set or fractureof the material.

6. An ice freezing tray comprising a body of thermoplastic materialformed into a plurality of compartments, each compartment havingindividual walls including'side and bottom walls, the side walls oi.'adjoining compartments being joined together along their upper edges.said material and saidwalls being flexible to cause the wallstemporarily to deform andl thereafter to return to their normalcondition whereby to release the frozen mass in each compartment whensaid body is gripped at opposite ends and torsionally twisted, thematerial along the upper edges where said walls are joined transmittingsaid torsional twist through the entire body, and segments connectingcertain of said walls of said compartments tending to distribute thetorsional twist throughout the body to assure a flexing of the walls ofsaid compartments without distortion of the material that will cause apermanent set or fracture of the material.

7. An ice freezing tray comprising a body of thermoplastic materialcharacterized by a resiliency permitting flexing to free the ice,separately formed compartments having their walls integrally formed andintegrally united along their top edges to the walls of adjacentcompartments, the walls between adjacent compartments below said topedges being separated by air spaces to provide for individually exposedheat conducting surfaces for each compartment, said body being twistableto flex said walls suillciently to free the bodies of ice in saidcompartments. and means connecting certain of said walls of saidcompartments, said means limiting the twisting and tending thereby toprevent distortion or fracture of said body.

8. A non-frost forming and non-ice adhering freezing tray comprisingindividual cube-forming compartments arranged in parallel rows, saidcompartments having individual but integrally connected walls and havingtheir upper edges common with one another, said walls being entirely ofa resilient thermoplastic material, the opposing walls of adjacentcompartments of each row being spaced from each other with air spacestherebetween, said tray Walls and said thermoplastic material being ofsuch character as to effect substantially complete release of the frozenmaterial individually from each compartment or from all of thecompartments at one time by manually gripping the ends of the tray andtorsionally twisting the tray to flex said Walls, and portionsofflexible thermoplastic material disposed on veach side of thelongitudinal center line of the tray and bridging said air spaces forconnecting certain of the Walls of adjacent compartments, said portionstending to transmit said .torsional twist of the tray when flexedmanually without distortion of the material that will cause a permanentset or fracture of the material.

9. A non-frost forming and non-ice adhering freezing tray comprisingindividual cube-forming compartments having individual but integrallyconnected walls spaced from each other on all sides but having theirupper edges common with one another, said walls being entirely of aresilient thermoplastic material and being self-sustaining when saidcompartments are filled with water, said tray walls and saidthermoplastic material being of such character as to effectsubstantially complete release of the frozen material individually fromeach compartment or from all of the compartments at one time by manuallygripping the ends of the tray and torsionally twisting the tray to flexsaid walls, and a row of segments of said thermoplastic materialdisposed in a plane parallel to the longitudinal axis of said tray andconnecting opposing walls of adjoining compartments for a portion of thedepth of said compartments.

10. A non-frost forming and non-ice adhering freezing tray comprisingindividual cube-forming compartments having individual but integrallyconnected walls spaced from each other on all sides but having theirupper edges common with one another, said walls being entirely of aresilient thermoplastic material and self-sustaining when saidcompartments are filled with water, said tray walls and saidthermoplastic material being of such character as to effectsubstantially complete release of the frozen material individually fromeach compartment or from all of the compartments at one time by manuallygripping the ends of the tray and torsionally twisting the tray to flexsaid walls, and segments of said thermoplastic material disposed on eachside of and substantially parallel to the longitudinal center line ofsaid tray and connecting opposing walls of adjoining compartments for aportion of the depth of the compartments.

11. An ice freezing tray comprising a body of thermoplastic materialcharacterized -by a resilassaaio iency permitting flexing to free theice, separately formed compartments having their walls integrally formedand integrally united along .their top edges to the walls of adjacentcompartments, the walls between adjacent compartments below their topedges being separated by. air spaces to provide for individually exposedheat conducting surfaces for each compartment, said body being twistableby a manual gripping of the tray at its ends to flex said walls to freethe bodies ofvice in said compartments, and portions of thermoplasticmaterial disposed on each side of the longitudinal center line of saidtray and bridging said air spaces for connecting certain of the walls ofadjoining compartments, said portions of thermoplastic material tendingto transmit a torsional twist to ex said walls when said tray ismanually 10 when said compartments are iilled with liquid, :the topportions of said compartments where said walls are joined cooperating toproduce a formation that will transmit an endwise torsional twist of thetray through all of said walls to distort the normal shape crosssectionally of each compartment whereby to loosen frozen material ineach compartment.

13. The freezing tray of claim 12 wherein the material is an ethylcellulose composition.

14. The freezing trayvof claim 12 wherein the material is a celluloseacetate composition..

JOSEPH A. GITS.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number` I Name Date 1,407,614 Wicks Feb. 21, 19221,803,734 Scherer May 5, 1931 1,868,070 Newman ....yJuly 19,19321,923,522 Whitehouse Aug. 22, 1933 2,035,679 Thompson Mar. 31. 19362,145,719 Geyer c Jan. 31, 1939 2,193,342 Price Mar. 12, 1940 2,323,486Pizarro July 9, 1943 2,386,979 Rundell Oct. 16, 1945

